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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
<head>
<style>
p.uppercase{
    text-transform: uppercase;
}
p.lowercase{
    text-transform: lowercase;
}
p.capitalize{
    text-transform: capitalize;
}
</style>
</head>
<body>
    <p class="uppercase">这是一些文本.</p>
    <p class="lowercase">这是一些文本2.</p>
    <p class="capitalize">这是一些文本3.</p>
</body>
</html>